LP F I-SUPPLEMENT PROPOSED FOR THE QUARTERLY JOURNAL OF THE GEOLOGICAL SOCIETY (This should be added to the discussion, page 216, Vol. lxiii.) Criticisms of three papers on the Zambezi Gorge, by Mr. G. W. Lamplugh, F. G. S., F. R. S.* No apology is needed for this discussion of a subject so close y related to the present writer's long-continued and w^ 1 , le ^ in ^stigations on a kindred subject in America. While Mr Lamplugh's treatment of the local features mav not be without interest, characteristics appear which should not be passed without criticism. For specialists, in even other branches of Geology, these may be of little interest with accordingly a disposition to accept the author, as would be the case with a text-book maker, who is not an investigator of related phenomena ; especially as the author made his short visit under the auspices of the British As- vahfe 10 "' glVing ^ a qU3Si endorseme nt of apparent As great water-falls are of unusual interest to the present writer he turned to Mr. Lamplugh's accounts of the fea- tures about the Victoria Falls, expecting to find more defi- nite information than he had previously obtained— for the author stated that his time had been devoted to two problem8--(l) "Origin of the Falls and the singularly erratic conformation below the Falls, and (2) the course of the river tor 70-80 miles below the Falls.f Investi^aHons showing the character of the rocks penetrated, the nature o the cataract descending over the side of its -or-e i„ place of at the end, and the magnitude of the falls" are those ot greatest importance in making comparative studies where they bear upon the principles of river erosion. nfTfc * f ? t ^°° f hi8 P a l^rsare: "On an Investigation of the Batoka Gorge," and "On the Geology of the Zam- Geology of the Zambezi Basin around the Batoka Gorgef" Q T <J. b. VOL 1X111, pp. l62-2l6, I97. S ^' J ' Ceol h To^r rg vT d BaSin ° f the Zambezi bel °w the Victoria Falls," IB A Re' on XXX1 ' PP * I33_I52 atld 28 7-303, 1908. : 3 9004 01511169 5012 jSf07 bezi Basin around the Batoka Gorge. ' ' Where is the Batoka Gorge and what is it ? The name is found to be an inven- tion of Mr. Lamplugh for the gorge into which the Victoria Falls descend, as discovered by Livingstone. It is simply THE gorge of the Zambezi, but as there are also rapids some distance above, it had been specifically designated the ''Grand Canon of the Zambezi " by Molyneux. There was nothing more needed to be said. The Geograph- ical Congress expresses thus the Golden Rule of nomen- clature, which underlies research; — "The name applied by the first discoverer should be used. . . . The arbitrary altering of . . . names, well known not only in common use, but also in science, is to be regarded as extremely un- advisable, and every means should be employed to resist such alteration," as also inappropriate and fantastic names*. Any one who has heard of Victoria Falls would immediately associate the term gorge or canon of the Zambezi with them, while Lamplugh's designation is inappropriate, con- fusing, with a pretentious disregard of what others had done and their rights. This casts a shadow over the whole of his work. From neither Mr. Lamplugh's descriptions, maps nor illustrations did it seem possible to understand the "erratic conformation of the gorge,'' which investigation was avow- edly the authors's first purpose. It was, however, most lucidly explained in the telling map, well selected and speaking photographs, and the text of the concise and ideal paper by Mr. Molyneux, f one of the African Geologists. Molyneux shows that the falls are absolutely unique, and not comparable in their recession with any other cataract, and also that they cannot furnish measurements for the rate of recession, such as he recognizes could be done at Ni- agara. His classic work antidated Mr. Lamplugh's visit to Africa. Livingstone and others had supposed that the gorge was due to fracture caused by internal earth forces. So far as he went his conjecture was correct, for Molyneux had dem- onstrated that the "erratic conformation " is due to jointed structure of the basalts, covered with a mantle of sand, while he further shows that these joints were opened by the river. When adding this feature, Molyneux speaks with deference of the great explorer. Not so did Mr. Lamplugh, in repeating these later observations, as if so hungry for fame that he could not resist a fragment that might be wedged off Livingstone. Name-invention other- wise than mentioned here, and changes of spelling appear *Geographical Journal, p. 63, Vol. xxv, 1905. i"The Physical History of the Victoria Falls," by A. J. C. Mo- lyneux, Geog. Jour., Vol. xxv, pp- 4o~55> 1905. in other pages of the author's writings, as if they counted for research. Mr. Lamplugh visited some five points along the gorge, one or two of which had not been reported by white men, but everywhere he found the gorge cut out of basalts, over- laid with sand, as had been supposed. He also noticed the breaking down of the walls of the gorge but there is the regrettable absence of measurements and cross sections, so that one can only see the development of the gorge in the strata through the eyes of the hurried traveller, in a field of continental phenomena new to himself. Of five subjects considered in his "Summary and Con- clusions," four may be passed over as conclusions mostly common to all the observers and of local value. The other bears upon the Age of the basalts, an important question, as out of them the gorge is cut. He discredits the evi- dence of their Tertiary age offered by Mennell and Molyn- eux. Then he remarks (p. 196) that the ground for Passarge thinking the rocks of Mesozoic age, is on "a highly speculative basis," and without showing more defi- nite data, he himself says that the basalts form "great series of lava-flows of undetermined age, but probably Mesozoic," and this, repeated alone in his Summary (p. 206) without further explanation is likely to be adopted by a text-book maker, with the consequent diffusion of ignorance or error. Other examples of his speculations may be given. The mantle of sands overlying the basalts is older than the streams, according to Molyneux, who is probably correct. But Lamplugh says that the sands attained their present position subsequent to the erosion of the [tributary] valleys, and that there are no dunes, but only a flat surface, and adds (p. 201) "The hypothesis that the}' have been wind- blown under conditions different to those which now prevail, agrees best with the general characteristics." He does not tell how he knows that they are eolian, or how the action of the wind differed in former times, nor does he show how stream banks are built up after the waters are flowing. Again, the waters of the Zambezi are remarkably clear. but the author remarks upon the greenish hues in the gorge below, and says that it "is probably due to the presence of organisms [tenderly] nurtured in the placid reaches above the Falls . . . and is more marked in the upper part of the canon ... we may suppose that the colouring agent is partly eliminated by the swift current and aerating rapids of the gorge. "* This is offered as a scientific contribution without giving any evidence of such organisms in the clear water of the upper river, which *Geog. Journal, p. 144, Vol. xxxi. coulgl be so bruised in their descent over the cataract, as to colour the water, and then to be burned up by the oxygen in the inferior rapids below. These features of the paper remind one of the man who never referred to himself with- out raising his own hat. The observations of value in his papers may be consulted by those locally interested, but they should be studied along with the labours of the African geologists. Mr. Lamplugh had special assistance of local value from Mr. Sykes, and Mr. Molyneux has later mentioned one or two stratigraphic points discussed by the author. Every writer makes mistakes; erroneous hypotheses built up on incom- plete evidence often lead to final correct solutions. These should be generously treated. Yet such unsupported specu- lationsand other features as heres*hown are based upon Mr. Lamplugh 's hurried trek of 600 miles, on foot and by beast, within a month, with a little longer stay at the Falls, and leaves the impression that the severally published papers, covering 105 pages, are the work of an "official chair- warmer, who has put into ponderous tomes the conclusions of others, and imagines that bibliographic discovery and revision constitutes original research." The council, of which he was a member, unfortunately took him at his own valuation. Our friend, Mr. Lamplugh, seems to have wandered from the parish, which had been ransacked by a hundred observers before, to a broad geological empire, with features on a scale not thought of at home, and others entirely new, in which he had inefficient training and lacked experience. But at home the author shows some similar character- istics, as in his B. A. address, at York (1906).* In this paper he tells with pseudo-modesty, how as a young man he ventured " to contribute my [his] mite towards the right understanding of the Yorkshire drift," and later attempts to quarantine Prof. James Geikie for being a polyglacialist, although this gentleman's classification is more or less in accord with common opinions in America and the Alps than is that of Mr. Lamplugh. The characteristics, mentioned above, would be ignored did the author not belittle the labours of others, as if wish- ing to seem wise at their expense. Accordingly his opin- ions and logic applied especially to the physics of Niagara, or other falls is of no value whatever, when not accom- panied by supporting evidence. J. W. Spencer, M. A., Ph. D., F. G. S., Investigator of the Evolution of the Falls of Niagara, and Origin of the Great Lakes of America. f *B. A. Report, 1906, p. 535 et al. tLate Special Commissioner of the Geological Survey of Canada for the Scientific Investigation of Niagara Falls.